If you're on a tight budget, you can get one of those 'multi-effects' pedals. But, if you really want the true taste of a dedicated (distortion, delay, reverb, and just about any) pedal, you need to buy a dedicated pedal. Check out this Reddit thread for further reading.

I mostly use a BOSS AC-3 acoustic simulator pedal, a Boss DS-1X distortion pedal, and a Electro-Harmonix Soul Food transparent overdrive pedal.